The present disclosure generally relates to voltage regulator circuits. In particular, this disclosure relates to adding a low-current voltage level to an existing voltage level of a voltage regulator circuit.
A voltage regulator is an electronic device or system designed to receive an input voltage and automatically maintain a constant voltage level on one or more output terminals. Depending on the design, a voltage regulator can be used to regulate one or more alternating current (AC) or direct current (DC) voltages. Voltage regulators can be included in electronic devices such as computer power supplies where they can be used to stabilize DC voltages used to supply power to electronic components such as processor(s), memory devices, and other types of integrated circuits (ICs). A voltage regulator circuit can receive a feedback voltage received from a sense point located adjacent to electronic component(s) that the voltage regulator supplies power to. This feedback voltage can be used to modulate an output voltage of the voltage regulator. This modulated output voltage can result in the voltage received by the supplied electronic component(s) being maintained at a stable value regardless of the current draw of the components or voltage drop across conductors interconnecting the voltage regulator to the components.
A field-effect transistor (FET) is a transistor that uses an electric field to control the shape and hence the conductivity of a channel of one type of charge carrier in a semiconductor material. FETs can be unipolar transistors as they can involve single-carrier-type operation. FETs can be majority-charge-carrier devices, in which the current flow is carried predominantly by majority carriers, or minority-charge-carrier devices, in which the current is mainly due to a flow of minority carriers. A FET device can consist of an active channel through which charge carriers, electrons or holes, flow from a source to a drain. Source and drain terminal conductors can be connected to the semiconductor through ohmic contacts. The conductivity of the channel can be a function of the electric potential applied across the gate and source terminals.